Question

Identify the type of reaction :

${\mathrm{PCl}}_5\rightleftharpoons {\mathrm{PCl}}_3+{\mathrm{Cl}}_2$

Answer 1

$\underset{\mathrm{Phosphorus}\mathrm{pentachloride}}{{\mathrm{PCl}}_5\left(\mathrm{s}\right)}\stackrel{∆}{\rightleftharpoons }\underset{\mathrm{Phosphorus}\mathrm{trichloride}}{{\mathrm{PCl}}_3\left(\mathrm{l}\right)}+\underset{\mathrm{Chlorine}}{{\mathrm{Cl}}_2\left(\mathrm{g}\right)}$

• Phosphorous pentachloride is decomposing into Phosphorous trichloride and Chlorine.
• It is an example of a thermal decomposition reaction.

Thermal decomposition- A thermal decomposition reaction requires energy to be supplied to the reactants in the form of heat. Such reactions are generally endothermic since energy is required to break the chemical bonds and separate the constituent elements.